一起来看看python的装饰器代码

def wrapper(fn):
    def inner(*args, **kwargs):
        ret = fn(*args, **kwargs)
        return ret
    return inner

"""
1.函数可以当参数传递
2.函数可以作为返回值进行返回
3.函数名称可以当成变量一样进行赋值操作
装饰器本质上是个闭包
在不改变原有函数调用的情况下,给函数增加新的功能
"""

#!/usr/bin/python
def admin(game):
    def inner(*args, **kwargs):  # inner添加了参数,args 一定是个元组 kwargs 一定是字典
        print('打开Wg')
        result = game(*args, **kwargs)  # * ** 表示把args元组和kwargs打散成位置参数,关键字参数传递进去
        print('关闭Wg')
        return result
    return inner
@admin
def play_dnf(username, password):
    print(f'开始玩DNF,账号:{username},密码:{password}')
    print('刀斩肉身,心斩灵魂')
    return '掉落:戮蛊的哀鸣炮'
@admin
def play_wow(race, occupation, server_name, camp):
    print(f'开始玩魔兽世界,种族:{race},职业:{occupation},服务器:{server_name},阵营:{camp}')
    print('为了辛多雷的荣耀')
    return '掉落:灰烬使者'
if __name__ == '__main__':
    ret1 = play_dnf('大马猴', '888888')
    print(ret1)
    ret2 = play_wow('血精灵', '圣骑士', '回音山', '部落')
    print(ret2)

python demo.py
打开Wg
开始玩DNF,账号:大马猴,密码:888888
刀斩肉身,心斩灵魂
关闭Wg
掉落:戮蛊的哀鸣炮
打开Wg
开始玩魔兽世界,种族:血精灵,职业:圣骑士,服务器:回音山,阵营:部落
为了辛多雷的荣耀
关闭Wg
掉落:灰烬使者
Process finished with exit code 0

#!/usr/bin/python
def wrapper1(fn):
    def inner(*args, **kwargs):
        print('这是w1进入')
        ret = fn(*args, **kwargs)
        print('这是w1出去')
        return ret
    return inner
def wrapper2(fn):
    def inner(*args, **kwargs):
        print('这是w2进入')
        ret = fn(*args, **kwargs)
        print('这是w2出去')
        return ret
    return inner
@wrapper1
@wrapper2
def target():
    print('我是目标')
if __name__ == '__main__':
    target()

# w1 w2 target w2 w1

def use_logging(level):
    def decorator(func):
        def wrapper(*args, **kwargs):
            if level == "warn":
                logging.warn("%s is running" % func.__name__)
            elif level == "info":
                logging.info("%s is running" % func.__name__)
            return func(*args)
        return wrapper
    return decorator
@use_logging(level="warn")
def foo(name='foo'):
    print("i am %s" % name)
foo()

class Foo(object):
    def __init__(self, func):
        self._func = func
    def __call__(self):
        print ('class decorator runing')
        self._func()
        print ('class decorator ending')
@Foo
def bar():
    print ('bar')
bar()